loadFromBag crashes in ROS2 when bag contains multiple topics

[afrixs]

I guess that topic parameter was meant to be used, e.g.

if (bag_message->topic_name != topic) {
  continue;
}

could be added here

[Ryanf55]

Thanks for the report. I've confirmed this is an issue with the following process on rolling today.

I ran two talker nodes:

ros2 run demo_nodes_cpp talker --ros-args -r chatter:=chatter1

ros2 run demo_nodes_cpp talker --ros-args -r chatter:=chatter2

I then recorded a bag with ros2 bag record --all

$ ros2 bag info rosbag2_2024_02_16-00_42_25/

Files:             rosbag2_2024_02_16-00_42_25_0.mcap
Bag size:          23.2 KiB
Storage id:        mcap
ROS Distro:        rolling
Duration:          4.99s
Start:             Feb 16 2024 00:42:25.111 (1708069345.111)
End:               Feb 16 2024 00:42:29.210 (1708069349.210)
Messages:          43
Topic information: Topic: /chatter2 | Type: std_msgs/msg/String | Count: 4 | Serialization Format: cdr
                   Topic: /chatter1 | Type: std_msgs/msg/String | Count: 4 | Serialization Format: cdr
                   Topic: /events/write_split | Type: rosbag2_interfaces/msg/WriteSplitEvent | Count: 0 | Serialization Format: cdr
                   Topic: /parameter_events | Type: rcl_interfaces/msg/ParameterEvent | Count: 0 | Serialization Format: cdr
                   Topic: /rosout | Type: rcl_interfaces/msg/Log | Count: 35 | Serialization Format: cdr

By default in rolling, the storage type for bags is mcap, but LoadFromBag hard codes the type as sqlite3.

Thus, trying again with specifying a sqlite3 type:

ros2 bag record --all -s sqlite3

And, finally the test code:

TEST(RosbagHandling, multipleTopics)
{

  std::string pathToBag = "/home/ryan/Dev/rosbag2_2024_02_16-00_50_47";
  string topic = "chatter1";
  GridMap gridMapOut;
  rcpputils::fs::path dir(pathToBag);

  EXPECT_TRUE(GridMapRosConverter::loadFromBag(pathToBag, topic, gridMapOut));
}

I got this result from colcon test:

2: [ RUN      ] RosbagHandling.multipleTopics
2: [INFO] [1708069934.957041361] [rosbag2_storage]: Opened database '/home/ryan/Dev/rosbag2_2024_02_16-00_50_47/rosbag2_2024_02_16-00_50_47_0.db3' for READ_ONLY.
2: 
2: >>> [rcutils|error_handling.c:108] rcutils_set_error_state()
2: This error state is being overwritten:
2: 
2:   'Handle's typesupport identifier (rosidl_typesupport_cpp) is not supported by this library, at ./src/type_support_dispatch.hpp:111'
2: 
2: with this new error message:
2: 
2:   'Fast CDR exception deserializing message of type grid_map_msgs::msg::dds_::GridMap_., at ./src/type_support_common.cpp:118'
2: 
2: rcutils_reset_error() should be called after error handling to avoid this.
2: <<<

[Ryanf55]

I've tried determining where it's throwing, but the tutorial I wrote for debugging tests with gdb doesn't isolate it.

But, you can instead just run gdb build/grid_map_ros/grid_map_ros-test

>>> catch throw
>>> run 
>>> bt

Thus, it's failing to deserialize, probably because it's the wrong type. This may be a different bug than you saw, but that's obviously wrong and should be fixed.

serialization.deserialize_message(&extracted_serialized_msg, &extracted_gridmap_msg);

I haven't used the rosbag API's, so it may take me a bit to get familiar with it. Anyone is welcome to issue a patch.
For some reason, even though building in debug mode, I can't inspect locals.

This reference doesn't help much for getting symbols.
https://stackoverflow.com/questions/26581066/how-to-get-backtrace-information-from-exception-in-googletest

[Ryanf55]

I also tried using VSCode to debug grid_map_ros, but had no luck. Here's the config which has the same issue about no symbols in GridMapRosCoverter.cpp. VSCode ignores breakpoints in there.

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "(gdb) Launch",
            "type": "cppdbg",
            "request": "launch",
            "program": "${workspaceRoot}/build/grid_map_ros/grid_map_ros-test",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${fileDirname}",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
            "setupCommands": [
                {
                    "description": "Enable pretty-printing for gdb",
                    "text": "-enable-pretty-printing",
                    "ignoreFailures": true
                },
                {
                    "description": "Set Disassembly Flavor to Intel",
                    "text": "-gdb-set disassembly-flavor intel",
                    "ignoreFailures": true
                }
            ]
        }

    ]
}